It's tough to predict the future, but it's very likely that he would split the Republican vote and make it easier for a Democrat to win in 2016.
Its a story we tell in 2305 when we discuss the consequences of the use of winner take all elections in the US and their tendency to lead to the formation of two large political parties. Efforts to support third party - or independent candidates can tip the scales in unusual ways. It's an odd consequence of a party getting a bit too big and when the factions within the party become hostile to one another.
Support can be thrown to someone running outside the party, or a party member may choose to run independently. It happens from time to time. The is is covered in class notes, but examples include:
Ralph Nader in 2000
Ross Perot in 1992 and 1996
John Anderson in 1980
George Wallace in 1968
And on through history. The problem with this can be that supporters of the outsider might end up with their least preferred option in office. Nader voters helped elect W. Bush. Perot voters helped elect Clinton.
Might we see a repeat in 2016 if Trump runs as an independent?
Some thoughts from the smart set:
- Politico: Defiant Donald Trump refuses to rule out third-party run.
- Business Insider: 5 things to consider as Donald Trump dangles a third-party run for president.
- RCP: Why Republicans Shouldn't Fear a Third-Party Trump.